Answer:
Vague Pronoun-She
Explanation:
Pronouns are a part of speech that replaces a noun. Pronoun examples are she, her, he, him, etc. The only pronoun in this sentence is "She" so it would be the Vague Pronoun.
"For how many days has this oven not been working," asked the repairman.
It is important because the sources tell you whether the article was credible. When you have an article that has bad source, you are running the risk of having, wrong, opinionated data. This can discredit you paper if you use it.
The sentence that sounds the best when you read it out loud is:
C. Summer vacation came as a relief to the student, who was tired of studying and writing research papers.
If you read all the sentences out loud they all sound weird except for this one.